CAZ-AVI Disk Study

Assessment of Susceptibility of Clinical Enterobacterales and Pseudomonas aeruginosa Isolates to Ceftazidime-Avibactam in Russia Using Local Testing Results by Disk Diffusion Method


Study Objective:

To assess the in vitro activity of ceftazidime-avibactam combination against clinical Enterobacterales and Pseudomonas aeruginosa isolates in various regions of Russia based on results of local susceptibility testing by disk diffusion method


Bacterial isolates: 22 121
  Enterobacterales: 17 456
  Pseudomonas aeruginosa: 4 665
Stage I: November 11, 2018 - April 28, 2019
Stage II: January 01, 2020 - December 28, 2020
Participating centers: 160 hospitals in 61 cities of Russian Federation

Inclusion Criteria:

Consecutive, non-duplicate (one per patient) clinical isolates of Enterobacterales and P. aeruginosa isolated from patients with clinical and laboratory signs of infections of different sites (intraabdominal, respiratory, skin and soft tissue, bones and joints, urinary, bloodstream, and CNS).

Exclusion Criteria:

  • Isolates other than Enterobacterales and P. aeruginosa;
  • Repeated isolates of the same species isolated from the same patient;
  • Colonizing isolates isolated from patients without clinical signs of infection or from the environment for infection control purposes;
  • Isolates for which the required information is the electronic CRF is missing or incomplete.

Study Procedures and Data Collection:

  • Isolation, species identification, and antimicrobial susceptibility testing of bacterial isolates is performed in the laboratories of the participating centers.
  • Information on the source of each isolate and its susceptibility to ceftazidime-avibactam (the diameter of inhibition zone around the disk) is entered into an electronic CRF.
  • Data on susceptibilities (zone diameters or MICs) to oxyimino-cephalosporins and/or carbapenems is entered into an electronic CRF, if available.
  • Data on the method(s) and result(s) of carbapenemase detection is entered into an electronic CRF, if available.
  • Susceptibility categories of isolates are determined automatically according to current EUCAST Clinical Breakpoints.

Study Coordinator

Interregional Association for Clinical Microbiology and Antimicrobial Chemotherapy IACMAC

Study Sponsor

Pfizer Inc.